package com.hmall.gateway.filter;

import com.hmall.common.exception.UnauthorizedException;
import com.hmall.common.utils.CollUtils;
import com.hmall.gateway.config.AuthProperties;
import com.hmall.gateway.util.JwtTool;
import lombok.RequiredArgsConstructor;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.AntPathMatcher;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

import java.util.List;

/**
 * author Link
 *
 * @version 1.0
 * @date 2025/3/12  11:28
 */
    @Component
    @RequiredArgsConstructor
    @EnableConfigurationProperties(AuthProperties.class)
    public class AuthGlobalFilter implements GlobalFilter, Ordered {

        private final JwtTool jwtTool;

        private final AuthProperties authProperties;

        private final AntPathMatcher antPathMatcher = new AntPathMatcher();

        @Override
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
            // 1.获取Request
            ServerHttpRequest request = exchange.getRequest();
            // 2.判断是否不需要拦截
            if (isExclude(request.getPath().toString())) {
                // 无需拦截，直接放行
                return chain.filter(exchange);
            }
            // 3.获取请求头中的token
            String token = null;
            List<String> headers = request.getHeaders().get("authorization");
            if (!CollUtils.isEmpty(headers)) {
                token = headers.get(0);
            }
            // 4.校验并解析token
            Long userId = null;
            try {
                userId = jwtTool.parseToken(token);
            } catch (UnauthorizedException e) {
                // 如果无效，拦截
                ServerHttpResponse response = exchange.getResponse();
                response.setRawStatusCode(401);
                return response.setComplete();
            }

            //5.如果有效，传递用户信息
            String userInfo = userId.toString();
            ServerWebExchange ex = exchange.mutate()
                    .request(b -> b.header("user-info",userInfo))
                    .build();

            // 6.放行
            return chain.filter(ex);
        }

        private boolean isExclude(String antPath) {
            for (String pathPattern : authProperties.getExcludePaths()) {
                if (antPathMatcher.match(pathPattern, antPath)) {
                    return true;
                }
            }
            return false;
        }

        @Override
        public int getOrder() {
            return 0;
        }
    }

